Customers are advised to obtain cash from “ATMs nationwide” or to seek “cash-back” on their debit cards.

A spokesman confirmed that cashless banking was being introduced across the entire NIB branch network over the next 18 months, and had already been introduced successfully in a number of branches. He said the feedback from customers was positive with few complaints.

“These branches provide better security for staff and allow us to spend more time, in a better setting, with our customers . . . Customers like them, as our staff have more time to discuss customers’ overall needs.”

However, NIB customer Frank Barry from Malahide described the change as hilarious and ridiculous: “A bank refusing to accept cash . . . I thought that’s what they are for?”

Mr Barry contacted The Irish Times after his wife Catherine Gralton received two letters informing her that the local branch would stop handling cash from next February.

“If I did have a cash lodgement, I would have to go to another bank, buy a bank draft and then go to NIB to lodge it,” he said.